1. Field of the Invention
The present invention relates to a throttle apparatus embedding an electronic control unit therein, and more particularly to a throttle apparatus of an engine, in which an electronic control unit is embedded within a throttle body, and a connector for connecting to an external portion is exposed to an outer portion of the throttle body.
2. Description of Related Art
In a fuel injection control system mounted to an engine having a comparatively compact and simple structure such as a general purpose engine or the like, there has been widely generalized a structure in which a fuel injection valve, an electronic control unit and the like are integrated with a throttle apparatus regulating an intake air amount. However, it is often the case that a spatial restriction exists in a portion at which the throttle apparatus is positioned, at a time of mounting the general purpose engine to the individual apparatus.
Accordingly, there has been attempted to downsize a whole size by efficiently arranging a plurality of parts necessary for opening and closing a throttle valve, such as a throttle apparatus described in Japanese Unexamined Patent Publication No. 2006-97500. However, since a connector for connecting to an external portion in an electronic control unit is determined an arranging direction on the basis of a terminal position of a circuit board embedded in the throttle body, and protrudes to an outer side largely from an outer wall of the throttle body, it is impossible to dissolve an interference of the connector with the other parts of the engine even if the throttle apparatus is made compact. Accordingly, there is generated a necessity for individually designing the throttle apparatus and the electronic control unit in which mounting positions and angles of the connector are set in correspondence to a spatial condition of the engine to which the throttle apparatus is mounted.
On the contrary, as a system in which the circuit boards for the electronic control are divided functionally so as to be arranged in parallel, and a plurality of connecting positions to the external portion are arranged in a lateral direction so as to be respectively connected to the connectors, such as an electronic control unit, for example, described in Japanese Unexamined Patent Publication No. 2001-282303, there has been proposed a structure in which a connection position arranged in a width direction on the connector can be optionally selected and set.
However, in this electronic control unit, a protruding direction of the connector is limited to one direction on the same plane in the throttle apparatus, and a position is changed within a width of the connector. Accordingly, no problem is generated in the case that a space is formed in a lower side of an air cleaner 50 and a connector 32 protruding from a throttle body 40 is fitted into the space, such as a throttle apparatus 10 shown in FIG. 4A, however, in the case that an air cleaner 51 protrudes to a lower side such as the throttle apparatus 10 shown in FIG. 4B, and the throttle apparatus corresponds to a type in which no space is formed in a lower side of the air cleaner 50 shown in FIG. 4A, the throttle apparatus 40 can not be used as it is.
Accordingly, in order to arrange the connector 32 in a lower side of an intake manifold 61 in an opposite side having a sufficient space, in FIG. 4B, there can be considered to change the structure of the throttle body 40 and the internal electronic control unit, however, a corresponding property and a general purpose property of the parts become low in these cases, and an increase of a cost is caused.